Pugs has targeted multiple VMs (JavaScript, Parrot, etc.) in the past, and we look forward to target more VMs in the future.

I've worked with CLR and YARV people to explore techniques in targetting them, and indeed both will probably become reasonable targets in their next release. I also plan to find some JVM people and see how much of JRE6 stuff we can use, but I'm not sure it's ready for Perl 6 yet.

As for Haskell: Pugs and Darcs have pushed GHC to improve its efficiency as a imperative VM, so it is becoming a really viable target for Perl 6.

However, with all that said, I think for the next few years, Perl 5 remains the most practical and robust VM to target, which is why Pugs now embeds Perl 5 by default. :-)